Maternal Depressive Symptom Trajectories and Psychosocial Functioning in Young Adults: A 27-year Longitudinal Study

Introduction

Maternal depression is a well-known risk factor for child development. Longitudinal studies extending from pregnancy to adulthood, however, are rare.

Objectives

The aim of the study was to investigate whether maternal high depressive symptom trajectories (chronic or intermittent depressive symptom patterns) from pregnancy to the adolescence of the children predict lower adaptive functioning or higher levels of emotional or behavioural symptoms in young adults.

Methods

The sample comprised 329 first-time mothers from maternity centres in Tampere, Finland. Maternal depressive symptoms were assessed with the Edinburgh Postnatal Depression Scale (EPDS) antenatally and at two months, six months, 4–5 years, 8–9 years and 16–17 years after delivery. A model including four symptom trajectories (very low, low-stable, high-stable and intermittent) was selected to describe the symptom patterns over time. Adaptive functioning and problems of the children (n = 144) were assessed by the Adult Self Report forms (Achenbach & Rescorla) at the age of 27 years.

Results

High maternal depressive symptom trajectories did not predict self-reported lower adaptive functioning of the children in adulthood. However, children of mothers with chronic or intermittent depressive symptom patterns reported higher levels of internalising problems as well as symptoms of depression and anxiety in young adulthood than the children of mothers with very low or low stable symptom patterns.

Conclusions

High maternal depressive symptom trajectories predict higher levels of emotional symptoms of children in young adulthood. The mechanisms of intergenerational transmission are important topics for further research.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

P2786Current ESC guidelines for normal ascending aortic diameter: prevalence of aortic dilatation increases to 20% in a consecutive coronary CTA population

Introduction

Epidemiological studies on the prevalence of ascending aortic (AA) dilatation are scanty.

Purpose

To clarify prevalence of AA dilatation according to ESC 2014 guidelines and to study its risk factors.

Methods

This retrospective study included 1000 consecutive patients scheduled for diagnostic coronary artery computer tomography angiography (CCTA) with low to moderate pretest probability for coronary artery disease (CAD). AA diameter was measured at 3 planes; sinus valsalva, sinotubular junction and tubular part. Threshold for AA dilatation was set to >40 mm (ESC 2014). Traditional risk factors for AA dilatation were collected from medical records.

Aortic size index (ASI) was used as a comparative measurement. ASI is defined as the ratio between aortic diameter and body surface area (BSA). The threshold for AA dilatation was set to upper limit of normal distribution exceeding two standard deviations (95%).

Heart-aorta angle (HAA, Figure) was measured as one suggestive risk factor.

Results

Patients' mean age was 52.9±9.8 years, 66.5% were women. The prevalence of AA dilatation in the whole study population was 20.4% according to ESC 2014 guidelines. When patients with hypertension (n=445) or coronary calcifications or stenosis in CCTA (n=375) were excluded, the prevalence of AA dilatation was 14.5% in the population of normotensive patients without CAD (n=380).

According to the normal-distributed ASI values the threshold for normal dimension of sinus valsalva was defined as 23.5 mm/m2 and for tubular part 22.7 mm/m2 for normotensive patients without CAD. Using these thresholds, the prevalence of AA dilatation was 7.8% in the whole population and 7.1% in normotensive patients without CAD.

Smaller HAA was associated to AA dilatation. Median HAA was 125.6° (range: 119.2–131.5°) in patients with dilated AA and 130.1° (123.7–136.4°) in patients with non-dilated AA (p<0.001).

Higher BSA was associated to larger AA dimensions. Risk factors for AA dilatation (according to ESC criteria) were male gender, BAV, hypertension and smoking (p<0.01).

Figure 1

Conclusions

The prevalence of AA dilatation proved to be relatively high in this consecutive CCTA population when using ESC 2014 guidelines. Body size is associated to AA dimensions; thus, it seems reasonable to include BSA in the definition of AA dilatation.

Acknowledgement/Funding

Oiva Vaittinen will grant, Aarne Koskelo Foundation

Chondrogenic differentiation of human bone marrow-derived mesenchymal stromal cells in a three-dimensional environment

Cell therapy combined with biomaterial scaffolds is used to treat cartilage defects. We hypothesized that chondrogenic differentiation bone marrow-derived mesenchymal stem cells (BM-MSCs) in three-dimensional biomaterial scaffolds would initiate cartilaginous matrix deposition and prepare the construct for cartilage regeneration in situ. The chondrogenic capability of human BM-MSCs was first verified in a pellet culture. The BM-MSCs were then either seeded onto a composite scaffold rhCo-PLA combining polylactide and collagen type II (C2) or type III (C3), or commercial collagen type I/III membrane (CG). The BM-MSCs were either cultured in a proliferation medium or chondrogenic culture medium. Adult human chondrocytes (ACs) served as controls. After 3, 14, and 28 days, the constructs were analyzed with quantitative polymerase chain reaction and confocal microscopy and sulfated glycosaminoglycans (GAGs) were measured. The differentiated BM-MSCs entered a hypertrophic state by Day 14 of culture. The ACs showed dedifferentiation with no expression of chondrogenic genes and low amount of GAG. The CG membrane induced the highest expression levels of hypertrophic genes. The two different collagen types in composite scaffolds yielded similar results. Regardless of the biomaterial scaffold, culturing BM-MSCs in chondrogenic differentiation medium resulted in chondrocyte hypertrophy. Thus, caution for cell fate is required when designing cell-biomaterial constructs for cartilage regeneration.

The Utilization of Freezing Steps in Mesenchymal Stromal Cell (MSC) Manufacturing: Potential Impact on Quality and Cell Functionality Attributes

Some recent reports suggest that cryopreserved and thawed mesenchymal stromal cells (MSCs) may have impaired functional properties as compared to freshly harvested MSCs from continuous cultures. A cryopreservation step in the manufacturing process brings important benefits, since it enables immediate off-the-shelf access to the products and a completion of all quality testing before batch release and administration to the patient. Cryopreservation is also inevitable in MSC banking strategies. In this study, we present the results from the MSC stability testing program of our in-house manufactured clinical-grade allogeneic bone marrow-derived MSC product that is expanded in platelet lysate and frozen in passage 2. The current manufacturing protocol contains only one freezing step and the frozen MSC product is thawed bed-side at the clinic. We can conclude superior viability and cell recovery of the frozen and thawed MSC product utilizing the validated freezing and thawing protocols we have developed. The MSC phenotype and differentiation potential was generally found to be unaltered after thawing, but the thawed cells exhibited a 50% reduced, but not completely abolished, performance in an in vitro immunosuppression assay. The in vitro immunosuppression assay results should, however, be interpreted with caution, since the chosen assay mainly measures one specific immunosuppressive mechanism of MSCs to suppress T-cell proliferation. Since at least two freezing steps are usually necessary in MSC banking strategies, we went on to investigate the impact of repeated freezing on MSC quality attributes. We can conclude that two freezing steps with a preceding cell culture phase of at least one passage before freezing is feasible and does not substantially affect basic cell manufacturing parameters or quality attributes of the final frozen and thawed product. Our results suggest, however, that an exhaustive number of freezing steps (≥4) may induce earlier senescence. In conclusion, our results support the utilization of frozen MSC products and MSC banking strategies, but emphasize the need of always performing detailed studies on also the cryopreserved MSC counterpart and to carefully report the cryopreservation and thawing protocols.

Extended HLA Haplotypes and Their Impact on DPB1 Matching of Unrelated Hematologic Stem Cell Transplant Donors

Although HLA-DPB1 has long been considered of lesser importance in the selection of an unrelated donor (URD) hematologic stem cell transplantation, currently in many instances the DPB1 type of the donor is relevant or even critical. At present, however, only a minority of registry donors are DPB1 typed. It is also unclear to what extent the DPB1 alleles are linked to the 5-locus HLA-A-, B-, C-, DRB1, -DQB1 haplotypes. We sought to study whether there is such a linkage by using donors in the Finnish Stem Cell Registry as the study population. The 6-locus HLA-A, -B, -C, -DRB1, -DQB1, -DPB1 haplotype frequencies were estimated from a group of 43,365 Finnish registry donors using the German National Bone Marrow Registry algorithm. Five-locus haplotype (HLA-A, -B, -C, -DRB1, -DQB1) and HLA-DPB1 allele frequencies were calculated as marginal frequencies of the estimated 6-locus haplotype frequencies. The Finnish average frequency of individual DPB1 alleles was compared with their respective frequencies in association with individual 5-locus HLA haplotypes (haplotype-specific frequencies). Finally, the probability of DPB1 matching in 10/10 matched URD transplants was assessed. Haplotype-specific DPB1 frequencies differed significantly from the average DPB1 frequencies in 81 of 100 most frequent Finnish 5-locus HLA haplotypes, including some infrequent DPB1 alleles that were associated almost exclusively with certain individual 5-locus haplotypes. Five-locus haplotypes that are enriched in Finland but rare among other Europeans carried stronger DPB1 associations than haplotypes that are frequent European-wide. Finally, 10/10 matched transplants from domestic registry donors were significantly more likely to also be DPB1 matched than those from foreign donors. The results indicate an extension of linkage disequilibrium in the MHC complex in the Finnish population. With continuing upfront DPB1 typing of registry donors, it will be possible to perform similar extended 6-locus haplotype frequency estimations also in other registries. The associations are likely to be population specific but may be weaker in more heterogeneous populations. In the future the results might be used to predict the probability of DPB1 match or permissive/nonpermissive DPB1 mismatch for non-DPB1 typed donors in registry donor searches.

The use of unlicensed bone marrow-derived platelet lysate-expanded mesenchymal stromal cells in colitis: a pre-clinical study

BACKGROUND

Mesenchymal stromal cells (MSCs) are a promising candidate for treatment of inflammatory disorders, but their efficacy in human inflammatory bowel diseases (IBDs) has been inconsistent. Comparing the results from various pre-clinical and clinical IBD studies is also challenging due to a large variation in study designs.

METHODS

In this comparative pre-clinical study, we compared two administration routes and investigated the safety and feasibility of both fresh and cryopreserved platelet-lysate-expanded human bone marrow-derived MSCs without additional licensing in a dextran sodium sulfate (DSS) colitis mouse model both in the acute and regenerative phases of colitis. Body weight, macroscopic score for inflammation and colonic interleukin (IL)-1β and tumor necrosis factor (TNF)α concentrations were determined in both phases of colitis. Additionally, histopathology was assessed and Il-1β and Agtr1a messenger RNA (mRNA) levels and angiotensin-converting enzyme (ACE) protein levels were measured in the colon in the regenerative phase of colitis.

RESULTS

Intravenously administered MSCs exhibited modest anti-inflammatory capacity in the acute phase of colitis by reducing IL-1β protein levels in the inflamed colon. There were no clear improvements in mice treated with fresh or cryopreserved unlicensed MSCs according to weight monitoring results, histopathology and macroscopic score results. Pro-inflammatory ACE protein expression and shedding were reduced by cryopreserved MSCs in the colon.

CONCLUSIONS

In conclusion, we observed a good safety profile for bone marrow-derived platelet lysate-expanded MSCs in a mouse pre-clinical colitis model, but the therapeutic effect of MSCs prepared without additional licensing (i.e. such as MSCs are administered in graft-versus-host disease) was modest in the chosen in vivo model system and limited to biochemical improvements in cytokines without a clear benefit in histopathology or body weight development.

Left atrial appendage morphology and relative contrast agent concentration in patients undergoing coronary artery CTA

AIM

To evaluate whether certain morphological features of the left atrial appendage (LAA) would influence the LAA/ascending aorta (AA) radiodensity ratio, as a reflection of the blood flow conditions in the LAA.

MATERIALS AND METHODS

Eight-hundred and eight consecutive patients undergoing computed tomography angiography (CCTA) were evaluated. Of these, 749 had no history of atrial fibrillation and none had suffered acute stroke. The LAA/AA radiodensity ratio, and the length, lobe number, and morphological classification of LAAs were assessed.

RESULTS

The distribution of morphological classes for LAAs were: windsock 62.3%, cactus 18.6%, chicken wing 10.0%, and cauliflower 9.2%. The mean LAA/AA radiodensity ratio was 0.87±0.14 (range 0.22-1.44). Female gender (p=0.001), elevated body mass index (BMI; r=-0.129; p=0.003), and diabetes (p=0.03) were associated with lower LAA/AA radiodensity ratios, while heart failure (p=0.017), significant coronary artery stenosis (p=0.010), and LAAs with multiple lobes (p=0.018), exhibited higher LAA/AA radiodensity ratios. Multiple regression analysis revealed that a short one-lobed cauliflower morphology was an independent predictor (p=0.007) of a decreased LAA/AA radiodensity ratio.

CONCLUSION

A decline in the LAA/AA radiodensity ratio may reflect decreased blood flow in the LAA, paralleling spontaneous echo contrast in transoesophageal echocardiography. Thus, CCTA might be of value in recognising LAA structures that predispose to decreased blood flow.

A microfluidic oxygen sink to create a targeted cellular hypoxic microenvironment under ambient atmospheric conditions

Physiological oxygen levels within the tissue microenvironment are usually lower than 14%, in stem cell niches these levels can be as low as 0-1%. In cell cultures, such low oxygen levels are usually mimicked by altering the global culture environment either by O₂ removal (vacuum or oxygen absorption) or by N₂ supplementation for O₂ replacement. To generate a targeted cellular hypoxic microenvironment under ambient atmospheric conditions, we characterised the ability of the dissolved oxygen-depleting sodium sulfite to generate an in-liquid oxygen sink. We utilised a microfluidic design to place the cultured cells in the vertical oxygen gradient and to physically separate the cells from the liquid. We demonstrate generation of a chemical in-liquid oxygen sink that modifies the surrounding O₂ concentrations. O₂ level control in the sink-generated hypoxia gradient is achievable by varying the thickness of the polydimethylsiloxane membrane. We show that intracellular hypoxia and hypoxia response element-dependent signalling is instigated in cells exposed to the microfluidic in-liquid O₂ sink-generated hypoxia gradient. Moreover, we show that microfluidic flow controls site-specific microenvironmental kinetics of the chemical O₂ sink reaction, which enables generation of intermittent hypoxia/re-oxygenation cycles. The microfluidic O₂ sink chip targets hypoxia to the cell culture microenvironment exposed to the microfluidic channel architecture solely by depleting O₂ while other sites in the same culture well remain unaffected. Thus, responses of both hypoxic and bystander cells can be characterised. Moreover, control of microfluidic flow enables generation of intermittent hypoxia or hypoxia/re-oxygenation cycles.

STATEMENT OF SIGNIFICANCE

Specific manipulation of oxygen concentrations in cultured cells' microenvironment is important when mimicking low-oxygen tissue conditions and pathologies such as tissue infarction or cancer. We utilised a sodium sulfite-based in-liquid chemical reaction to consume dissolved oxygen. When this liquid was pumped into a microfluidic channel, lowered oxygen levels could be measured outside the channel through a polydimethylsiloxane PDMS membrane allowing only for gaseous exchange. We then utilised this setup to deplete oxygen from the microenvironment of cultured cells, and showed that cells responded to hypoxia on molecular level. Our setup can be used for specifically removing oxygen from the cell culture microenvironment for experimental purposes and for generating a low oxygen environment that better mimics the cells' original tissue environments.

Mesenchymal Stromal Cells and Their Extracellular Vesicles Enhance the Anti-Inflammatory Phenotype of Regulatory Macrophages by Downregulating the Production of Interleukin (IL)-23 and IL-22

Resolution-phase macrophage population orchestrates active dampening of the inflammation by secreting anti-inflammatory and proresolving products including interleukin (IL)-10 and lipid mediators (LMs). We investigated the effects of both human bone marrow-derived mesenchymal stromal cells (MSCs) and MSC-derived extracellular vesicles (MSC-EVs) on mature human regulatory macrophages (Mregs). The cytokines and LMs were determined from cell culture media of Mregs cultivated with MSCs and MSC-EVs. In addition, the alterations in the expression of cell surface markers and the phagocytic ability of Mregs were investigated. Our novel findings indicate that both MSC coculture and MSC-EVs downregulated the production of IL-23 and IL-22 enhancing the anti-inflammatory phenotype of Mregs and amplifying proresolving properties. The levels of prostaglandin E2 (PGE2) were substantially upregulated in MSC coculture media, which may endorse proresolving LM class switching. In addition, our results manifest, for the first time, that MSC-EVs mediate the Mreg phenotype change via PGE2. These data suggest that both human MSC and MSC-EVs may potentiate tolerance-promoting proresolving phenotype of human Mregs.

Immunomonitoring of MSC-Treated GvHD Patients Reveals Only Moderate Potential for Response Prediction but Indicates Treatment Safety

Mesenchymal stromal cells (MSCs) are used as salvage therapy to treat steroid-refractory acute graft-versus-host disease (aGvHD). We studied the immunological response to MSC treatment in 16 aGvHD patients by assessing lymphocyte profiles and three proposed aGvHD serum markers during the MSC treatment. Surprisingly, there were no obvious differences in the lymphocyte profiles between the responders and non-responders. The numbers of T, B, and NK cells were below the normal reference interval in all patients. CD4⁺ T helper (Th) cell levels remained particularly low throughout the follow-up period. The relative proportion of Th1 cells decreased, while regulatory T cells remained unaltered, and only very few Th2 and Th17 cells could be detected. Serum concentrations of regenerating islet-derived protein 3-alpha, cytokeratin-18 fragments (CK18F), and elafin were significantly elevated in patient samples compared with healthy controls, but only CK18F showed any potential in the prediction of patients’ response to MSCs. No obvious markers for MSC therapy response were revealed in this study, but the results suggest that allogeneic MSCs do not provoke overt T cell-mediated immune responses at least in immunosuppressed aGvHD patients. The results advocate for the safety of MSC therapy and bring new insights in MSC immunomodulation mechanisms.

Automated image analysis detects aging in clinical-grade mesenchymal stromal cell cultures

BACKGROUND

Senescent cells are undesirable in cell therapy products due to reduced therapeutic activity and risk of aberrant cellular effects, and methods for assessing senescence are needed. Early-passage mesenchymal stromal cells (MSCs) are known to be small and spindle-shaped but become enlarged upon cell aging. Indeed, cell morphology is routinely evaluated during MSC production using subjective methods. We have therefore explored the possibility of utilizing automated imaging-based analysis of cell morphology in clinical cell manufacturing.

METHODS

An imaging system was adopted for analyzing changes in cell morphology of bone marrow-derived MSCs during long-term culture. Cells taken from the cultures at the desired passages were plated at low density for imaging, representing morphological changes observed in the clinical-grade cultures. The manifestations of aging and onset of senescence were monitored by population doubling numbers, expression of p16INK4a and p21Cip1/Waf1, β-galactosidase activity, and telomeric terminal restriction fragment analysis.

RESULTS

Cell area was the most statistically significant and practical parameter for describing morphological changes, correlating with biochemical senescence markers. MSCs from passages 1 (p1) and 3 (p3) were remarkably uniform in size, with cell areas between 1800 and 2500 μm2. At p5 the cells began to enlarge resulting in a 4.8-fold increase at p6-9 as compared to p1. The expression of p16INK4a and activity of β-galactosidase had a strong correlation with the increase in cell area, whereas the expression of p21Cip1/Waf1 reached its maximum at the onset of growth arrest and subsequently decreased. Mean telomere length shortened at an apparently constant rate during culture, from 8.2 ± 0.3 kbp at p1, reaching 6.08 ± 0.6 kbp at senescence.

CONCLUSIONS

Imaging analysis of cell morphology is a useful tool for evaluating aging in cell cultures throughout the lifespan of MSCs. Our findings suggest that imaging analysis can reproducibly detect aging-related changes in cell morphology in MSC cultures. These findings suggest that cell morphology is still a supreme measure of cell quality and may be utilized to develop new noninvasive imaging-based methods to screen and quantitate aging in clinical-grade cell cultures.

A European HLA Isolate and Its Implications for Hematopoietic Stem Cell Transplant Donor Procurement

Europeans have often been considered a homogenous group in registry donor match predictions, but it is now evident that HLA haplotype frequencies vary across the European continent. Earlier studies have indicated that Finns in northeastern Europe have unique HLA characteristics, and the increasing availability of high-resolution registry donor data is now making more detailed comparisons possible. In the first phase of the present study, estimated HLA haplotype frequencies in stem cell donor registries of Finland and its neighbors Sweden and Russia were calculated using the algorithm of the German National Bone Marrow Donor Registry (ZKRD) and their frequencies were compared with one another and also with that of Germany. Virtual donor searches for 1492 high-resolution typed Finnish patients in the Finnish, Swedish and German registries were then performed, using individual match predictions for each registry. In the last phase, the impact of specifically Finnish-enriched HLA haplotypes on Finnish patients and the use of Finnish registry donors was assessed by analyzing 647 consecutive hematopoietic stem cell transplantation (HSCT) donor searches and 40 exported Finnish HSCTs. The Finnish HLA landscape was more homogenous than the 3 other studied populations, but also genetically distinct from them. The match predictions found a probable 10/10 match for 71%, 41%, and 31% of the Finnish patients in the German, Finnish, and Swedish registries, respectively. Thirty-four of Finland's 100 most frequent HLA haplotypes were represented with a frequency of <.0003 in Germany, and with an 8- to 3262-fold greater frequency in Finland than in Germany. Patients carrying these Finnish-enriched haplotypes were less likely to receive a matched HSCT but more likely to receive it from a domestic donor. Registry donors carrying them were more likely to donate stem cells, both nationally and internationally. The Finnish HLA isolate has a significant impact on both Finnish patients and registry donors, explaining the high use of national registry donors for Finnish patients. Haplotype frequency estimations are an important tool for small registries as well, to help optimize donor match predictions and the size of individual registries.

Methylome Analysis of Human Bone Marrow MSCs Reveals Extensive Age- and Culture-Induced Changes at Distal Regulatory Elements

Human bone marrow stromal cells, or mesenchymal stem cells (BM-MSCs), need expansion prior to use as cell-based therapies in immunological and tissue repair applications. Aging and expansion of BM-MSCs induce epigenetic changes that can impact therapeutic outcomes. By applying sequencing-based methods, we reveal that the breadth of DNA methylation dynamics associated with aging and expansion is greater than previously reported. Methylation changes are enriched at known distal transcription factor binding sites such as enhancer elements, instead of CpG-rich regions, and are associated with changes in gene expression. From this, we constructed hypo- and hypermethylation-specific regulatory networks, including a sub-network of BM-MSC master regulators and their predicted target genes, and identified putatively disrupted signaling pathways. Our genome-wide analyses provide a broader overview of age- and expansion-induced DNA methylation changes and a better understanding of the extent to which these changes alter gene expression and functionality of human BM-MSCs.

Medical surveillance for occupational asthma-how are cases detected?

Background

In Finland, medical surveillance, including spirometry, is periodically performed for workers who are exposed to agents capable of causing occupational asthma (OA). Although it has been shown that surveillance can detect OA at an early stage, few studies have assessed its benefits or the role of surveillance spirometry.

Aims

To assess the role of surveillance and spirometry in detecting OA and to evaluate the quality of spirometry.

Methods

We retrospectively reviewed the medical files of patients in health surveillance programmes who were diagnosed with sensitizer-induced OA at the Finnish Institute of Occupational Health in 2012‒14. We collected information on work exposure, respiratory symptoms, healthcare visits that initiated the diagnostic process, first spirometry and other diagnostic tests.

Results

Sixty files were reviewed. Medical surveillance detected 11 cases (18%) and 49 cases (82%) were detected at doctors' appointments that were not related to surveillance. The median delay from the onset of asthma symptoms to diagnosis was 2.2 years. Delay did not differ between these groups. No cases were detected on the basis of abnormal spirometry without respiratory symptoms. However, five patients (8%) initially reported solely work-related rhinitis symptoms. Spirometry was normal in half of the cases and quality criteria were fulfilled in 86% of the tests.

Conclusions

Fewer than one in five OA cases were detected through medical surveillance. Investigations were initiated by respiratory symptoms. No asymptomatic worker was referred because of abnormal spirometry. Our results highlight the importance of work-related nasal symptoms in detecting OA.

Low interleukin-2 concentration favors generation of early memory T cells over effector phenotypes during chimeric antigen receptor T-cell expansion

BACKGROUND

Adoptive T-cell therapy offers new options for cancer treatment. Clinical results suggest that T-cell persistence, depending on T-cell memory, improves efficacy. The use of interleukin (IL)-2 for in vitro T-cell expansion is not straightforward because it drives effector T-cell differentiation but does not promote the formation of T-cell memory. We have developed a cost-effective expansion protocol for chimeric antigen receptor (CAR) T cells with an early memory phenotype.

METHODS

Lymphocytes were transduced with third-generation lentiviral vectors and expanded using CD3/CD28 microbeads. The effects of altering the IL-2 supplementation (0-300 IU/mL) and length of expansion (10-20 days) on the phenotype of the T-cell products were analyzed.

RESULTS

High IL-2 levels led to a decrease in overall generation of early memory T cells by both decreasing central memory T cells and augmenting effectors. T memory stem cells (T_SCM, CD95⁺CD45RO^-CD45RA⁺CD27⁺) were present variably during T-cell expansion. However, their presence was not IL-2 dependent but was linked to expansion kinetics. CD19-CAR T cells generated in these conditions displayed in vitro antileukemic activity. In summary, production of CAR T cells without any cytokine supplementation yielded the highest proportion of early memory T cells, provided a 10-fold cell expansion and the cells were functionally potent.

DISCUSSION

The number of early memory T cells in a T-cell preparation can be increased by simply reducing the amount of IL-2 and limiting the length of T-cell expansion, providing cells with potentially higher in vivo performance. These findings are significant for robust and cost-effective T-cell manufacturing.

Expression of neural cell adhesion molecule and polysialic acid in human bone marrow-derived mesenchymal stromal cells

BACKGROUND

In order to develop novel clinical applications and to gain insights into possible therapeutic mechanisms, detailed molecular characterization of human bone marrow-derived mesenchymal stromal cells (hBM-MSCs) is needed. Neural cell adhesion molecule (NCAM, CD56) is a transmembrane glycoprotein modulating cell-cell and cell-matrix interactions. An additional post-translational modification of NCAM is the α2,8-linked polysialic acid (polySia). Because of its background, NCAM is often considered a marker of neural lineage commitment. Generally, hBM-MSCs are considered to be devoid of NCAM expression, but more rigorous characterization is needed.

METHODS

We have studied NCAM and polySia expression in five hBM-MSC lines at mRNA and protein levels. Cell surface localization was confirmed by immunofluorescence staining and expression frequency in the donor-specific lines by flow cytometry. For the detection of poorly immunogenic polySia, a fluorochrome-tagged catalytically defective enzyme was employed.

RESULTS

All five known NCAM isoforms are expressed in these cells at mRNA level and the three main isoforms are present at protein level. Both polysialyltransferases, generally responsible for NCAM polysialylation, are expressed at mRNA level, but only very few cells express polySia at the cell surface.

CONCLUSIONS

Our results underline the need for a careful control of methods and conditions in the characterization of MSCs. This study shows that, against the generally held view, clinical-grade hBM-MSCs do express NCAM. In contrast, although both polysialyltransferase genes are transcribed in these cells, very few express polySia at the cell surface. NCAM and polySia represent new candidate molecules for influencing MSC interactions.

Osteogenic differentiation of mesenchymal stromal cells in two-dimensional and three-dimensional cultures without animal serum

INTRODUCTION

Bone marrow-derived mesenchymal stromal cells (MSCs) have been intensely studied for the purpose of developing solutions for clinical tissue engineering. Autologous MSCs can potentially be used to replace tissue defects, but the procedure also carries risks such as immunization and xenogeneic infection. Replacement of the commonly used fetal calf serum (FCS) with human platelet lysate and plasma (PLP) to support cell growth may reduce some of these risks. Altered media could, however, influence stem cell differentiation and we address this experimentally.

METHODS

We examined human MSC differentiation into the osteoblast lineage using in vitro two- and three-dimensional cultures with PLP or FCS as cell culture medium supplements. Differentiation was followed by quantitative polymerase chain reaction, and alkaline phosphatase activity, matrix formation and matrix calcium content were quantified.

RESULTS

Three-dimensional culture, where human MSCs were grown on collagen sponges, markedly stimulated osteoblast differentiation; a fourfold increase in calcium deposition could be observed in both PLP and FCS groups. PLP-grown cells showed robust osteogenic differentiation both in two- and three-dimensional MSC cultures. The calcium content of the matrix in the two-dimensional PLP group at day 14 was 2.2-fold higher in comparison to the FCS group (p < 0.0001), and at day 21 it was still 1.3-fold higher (p < 0.001), suggesting earlier calcium accumulation to the matrix in the PLP group. This was supported by stronger Alizarin Red staining in the PLP group at day 14. In two-dimesional PLP cultures, cellular proliferation appeared to decrease during later stages of differentiation, while in the FCS group the number of cells increased throughout the experiment. In three-dimensional experiments, the PLP and FCS groups behaved more congruently, except for the alkaline phosphatase activity and mRNA levels which were markedly increased by PLP.

CONCLUSIONS

Human PLP was at least equal to FCS in supporting osteogenic differentiation of human MSCs in two- and three-dimensional conditions; however, proliferation was inferior. As PLP is free of animal components, and thus represents reduced risk for xenogeneic infection, its use for human MSC-induced bone repair in the clinic by the three-dimensional live implants presented here appears a promising therapy option.

Differential Clearance of Rat and Human Bone Marrow-Derived Mesenchymal Stem Cells from the Brain after Intra-arterial Infusion in Rats

Intra-arterial (IA) delivery of bone marrow-derived mesenchymal stem cells (BM-MSCs) has shown potential as a minimally invasive therapeutic approach for stroke. The aim of the present study was to determine the whole-body biodistribution and clearance of technetium-99m (99mTc)-labeled rat and human BM-MSCs after IA delivery in a rat model of transient middle cerebral artery occlusion (MCAO) using single-photon emission computed tomography (SPECT). Our hypothesis was that xenotransplantation has a major impact on the behavior of cells. Male RccHan: Wistar rats were subjected to sham operation or MCAO. Twenty-four hours after surgery, BM-MSCs (2×106 cells/animal) labeled with 99mTc were infused into the external carotid artery. Whole-body SPECT images were acquired 20 min, 3 h, and 6 h postinjection, after which rats were sacrificed, and organs were collected and weighed for measurement of radioactivity. The results showed that the majority of the cells were located in the brain and especially in the ipsilateral hemisphere immediately after cell infusion both in sham-operated and MCAO rats. This was followed by fast disappearance, particularly in the case of human cells. At the same time, the radioactivity signal increased in the spleen, kidney, and liver, the organs responsible for destroying cells. Further studies are needed to demonstrate whether differential cell behavior has any functional impact.

A robust and reproducible animal serum-free culture method for clinical-grade bone marrow-derived mesenchymal stromal cells

Efficient xenofree expansion methods to replace fetal bovine serum (FBS)-based culture methods are strongly encouraged by the regulators and are needed to facilitate the adoption of mesenchymal stromal cell (MSC)-based therapies. In the current study we established a clinically-compliant and reproducible animal serum-free culture protocol for bone marrow-(BM-) MSCs based on an optimized platelet-derived supplement. Our study compared two different platelet-derived supplements, platelet lysate PL1 versus PL2, produced by two different methods and lysed with different amounts of freeze–thaw cycles. Our study also explored the effect of a low oxygen concentration on BM-MSCs. FBS-supplemented BM-MSC culture served as control. Growth kinetics, differentiation and immunomodulatory potential, morphology, karyotype and immunophenotype was analysed. Growth kinetics in long-term culture was also studied. Based on the initial results, we chose to further process develop the PL1-supplemented culture protocol at 20 % oxygen. The results from 11 individual BM-MSC batches expanded in the chosen condition were consistent, yielding 6.60 × 10⁹ ± 4.74 × 10⁹ cells from only 20 ml of bone marrow. The cells suppressed T-cell proliferation, displayed normal karyotype and typical MSC differentiation potential and phenotype. The BM-MSCs were, however, consistently HLA-DR positive when cultured in platelet lysate (7.5–66.1 %). We additionally show that culture media antibiotics and sterile filtration of the platelet lysate can be successfully omitted. We present a robust and reproducible clinically-compliant culture method for BM-MSCs based on platelet lysate, which enables high quantities of HLA-DR positive MSCs at a low passage number (p2) and suitable for clinical use.

Unexpected complication in a rat stroke model: exacerbation of secondary pathology in the thalamus by subacute intraarterial administration of human bone marrow-derived mesenchymal stem cells

This study examined whether human bone marrow mesenchymal stromal/stem cells (BMMSCs) could alleviate the secondary pathology in the thalamus after middle cerebral artery occlusion (MCAO) in rats. Atypical accumulation of both amyloid-β (Aβ) and calcium in the thalamus was significantly higher in rats receiving the BMMSCs infusion 48 hours after MCAO as compared with the vehicle MCAO group. The elevated Aβ/calcium accumulation correlated with the level of impaired sensorimotor function. Although secondary pathology in the thalamus seems to be rodent specific, it needs to be taken into account because it may impair long-term behavioral recovery and negate therapeutic treatment effects.

Recombinant human type II collagen hydrogel provides a xeno-free 3D micro-environment for chondrogenesis of human bone marrow-derived mesenchymal stromal cells

Recombinant human type II collagen (rhCII) hydrogel was tested as a xeno-free micro-environment for the chondrogenesis of human bone marrow-derived mesenchymal stromal cells (BM-MSCs). The rhCII hydrogels were seeded with BM-MSCs and cultured in a xeno-free chondro-inductive medium for 14, 28 and 84 days. High-density pellet cultures served as controls. The samples were subjected to biochemical, histological and gene expression analyses. Although the cells deposited glycosaminoglycans into the extracellular space significantly more slowly in the rhCII hydrogels compared to the high-density pellets, a similar potential of matrix deposition was reached by the end of the 84-day culture. At day 28 of culture, the gene expression level for cartilage marker genes (i.e. genes encoding for Sox9 transcription factor, Collagen type II and Aggrecan) were considerably lower in the rhCII hydrogels than in the high-density pellets, but at the end of the 84-day culture period, all the cartilage marker genes analysed were expressed at a similar level. Interestingly, the expression of the matrix metallopeptidases (MMP)-13, MMP-14 and MMP-8, i.e. extracellular collagen network-degrading enzymes, were transiently upregulated in the rhCII hydrogel, indicating active matrix reorganization. This study demonstrated that the rhCII hydrogel functions as a xeno-free platform for BM-MSC chondrogenesis, although the process is delayed. The reversible catabolic reaction evoked by the rhCII hydrogel might be beneficial in graft integration in vivo and pinpoints the need to further explore the use of hydrogels containing recombinant extracellular matrix (ECM) proteins to induce the chondrogenesis of MSCs. Copyright © 2015 John Wiley & Sons, Ltd.

Xeno-free chondrogenesis of bone marrow mesenchymal stromal cells: towards clinical-grade chondrocyte production

Current cell-based cartilage therapies relay on articular cartilage-derived autologous chondrocytes as a cell source, which possesses disadvantages, such as, donor site morbidity and dedifferentiation of chondrocytes during in vitro expansion. Due to these and other limitations, novel cell sources and production strategies are needed. Bone marrow-derived mesenchymal stromal cells (BM-MSCs) are a fascinating alternative, but they are not spontaneously capable of producing hyaline cartilage-like repair tissue in vivo. In vitro pre-differentiation of BM-MSCs could be used to produce chondrocytes for clinical applications. However, clinically compatible defined and xeno-free differentiation protocol is lacking. Hence, this study aimed to develop such chondrogenic differentiation medium for human BM-MSCs. We assessed the feasibility of the medium using three human BM-MSCs donors and validated the method by comparing BM-MSCs to three other cell types holding potential for articular cartilage repair. The effectiveness of the method was compared to conventional serum-free and commercially available chondrogenic differentiation media. The results show that the defined xeno-free differentiation medium is at least as efficient as conventionally used serum-free chondrogenic medium and performed significantly better on all cell types tested compared to the commercially available chondrogenic medium.

Toll-like receptors in human chondrocytes and osteoarthritic cartilage

BACKGROUND AND PURPOSE

Degenerating cartilage releases potential danger signals that react with Toll-like receptor (TLR) type danger receptors. We investigated the presence and regulation of TLR1, TLR2, and TLR9 in human chondrocytes.

METHODS

We studied TLR1, TLR2, TLR4, and TLR9 mRNA (qRT-PCR) and receptor proteins (by immunostaining) in primary mature healthy chondrocytes, developing chondrocytes, and degenerated chondrocytes in osteoarthritis (OA) tissue sections of different OARSI grades. Effects of a danger signal and of a pro-inflammatory cytokine on TLRs were also studied.

RESULTS

In primary 2D-chondrocytes, TLR1 and TLR2 were strongly expressed. Stimulation of 2D and 3D chondrocytes with a TLR1/2-specific danger signal increased expression of TLR1 mRNA 1.3- to 1.8-fold, TLR2 mRNA 2.6- to 2.8-fold, and TNF-α mRNA 4.5- to 9-fold. On the other hand, TNF-α increased TLR1 mRNA] expression 16-fold, TLR2 mRNA expression 143- to 201-fold, and TNF-α mRNA expression 131- to 265-fold. TLR4 and TLR9 mRNA expression was not upregulated. There was a correlation between worsening of OA and increased TLR immunostaining in the superficial and middle cartilage zones, while chondrocytes assumed a CD166(×) progenitor phenotype. Correspondingly, TLR expression was high soon after differentiation of mesenchymal stem cells to chondrocytes. With maturation, it declined (TLR2, TLR9).

INTERPRETATION

Mature chondrocytes express TLR1 and TLR2 and may react to cartilage matrix/chondrocyte-derived danger signals or degradation products. This leads to synthesis of pro-inflammatory cytokines, which stimulate further TLR and cytokine expression, establishing a vicious circle. This suggests that OA can act as an autoinflammatory disease and links the old mechanical wear-and-tear concept with modern biochemical views of OA. These findings suggest that the chondrocyte itself is the earliest and most important inflammatory cell in OA.

Collection, processing and testing of bone, corneas, umbilical cord blood and haematopoietic stem cells by European Blood Alliance members

BACKGROUND AND OBJECTIVES

A questionnaire study was carried out in collaboration with the European Blood Alliance (EBA) Tissues and Cells (T&C) working group. The aim was to assess the level of involvement and commonality of processes on the procurement, testing and storage of bone, corneas, umbilical cord blood (UCB) and haematopoietic stem cells (HSC) in order to identify different practices and to explore whether recommendations can be made for harmonization.

MATERIALS AND METHODS

An online questionnaire was used for data collection in 2011, and 43 replies were received covering 71 product answers from 13 countries.

RESULTS AND CONCLUSIONS

Estimated percentages of tissue and cell banking covered by EBA member blood banks as a proportion of all collections of each individual country varied markedly. There were also major differences in the amounts of products collected and discarded and in proportions tissues provided for grafting. However, discarding of certain collections also reflects the practice of increasing the likelihood of the very best units being used for transplantation. Harmonization of possible practices should focus on matching supply with demand and on identifying the most efficient operators. This could allow for the development of practices for minimizing unnecessary collections.

Human bone marrow mesenchymal stem/stromal cells produce efficient localization in the brain and enhanced angiogenesis after intra-arterial delivery in rats with cerebral ischemia, but this is not translated to behavioral recovery

Intravascular cell therapy is a promising approach for the treatment of stroke. However, high accumulation of cells to lungs and other filtering organs is a major concern after intravenous (i.v.) cell transplantation. This can be circumvented by intra-arterial (i.a.) cell infusion, which improves homing of cells to the injured brain. We studied the effect of i.a. delivery of human bone marrow-derived mesenchymal cells (BMMSCs) on behavioral and histological outcome in rats after middle cerebral artery occlusion (MCAO). Sixty male Wistar rats were subjected to transient MCAO (60 min) or sham-operation. BMMSCs (1×10(6)) were infused into the external carotid artery on postoperative day 2 or 7. Histology performed after a 42-day follow-up did not detect any human cells (MAB1281) in the ischemic brain. Endothelial cell staining with RECA-1 revealed a significant increase in the number of blood vessels in the perilesional cortex in MCAO rats treated with cells on postoperative day 7. Behavioral recovery as assessed in three tests, sticky label, cylinder and Montoya's staircase, was not improved by human BMMSCs during the follow-up. In conclusion, human BMMSCs did not improve functional recovery in MCAO rats despite effective initial homing to the ischemic hemisphere and enhanced angiogenesis, when strict behavioral tests not affected by repeated testing and compensation were utilized.

Laminin production and basement membrane deposition by mesenchymal stem cells upon adipogenic differentiation

The aim was to study laminin (LM) synthesis, integration, and deposition into the basement membrane (BM) during adipogenesis. Human bone marrow-derived mesenchymal stromal cells (MSCs) were induced along the adipogenic lineage. LM chain mRNA and protein levels were followed using quantitative real-time polymerase chain reaction (qRT-PCR), immunofluorescence (IF) staining, transmission electron microscopy (TEM), and immunoprecipitation. MSCs produced low levels of LM mRNAs but were not surrounded by BM in IF and TEM imaging. LM-α4, LM-β1, and LM-γ1 mRNAs increased during adipogenesis 3.9-, 5.8-, and 2.8-fold by day 28. LM-411 was immunoprecipitated from the ECM of the differentiated cells. Immunostaining suggested deposition of LM-411 and some LM-421. BM build-up was probably organized in part by integrin (Int) α6β1. At day 28, TEM images revealed BM-like structures around fat droplet-containing cells. The first signs of BM formation and Int α6β1 were seen using IF imaging at day 14. Laminin-411 and Int α6β1 were expressed in vivo in mature human subcutaneous fat tissue. Undifferentiated human MSCs did not organize LM subunits into BM, whereas LM-411 and some LM-421 are precipitated in the BM around adipocytes. This is the first demonstration of LM-411 precipitation during hMSC adipogenesis around adipocytes as a structural scaffold and Int-regulated signaling element.

Towards a global system of vigilance and surveillance in unrelated donors of haematopoietic progenitor cells for transplantation

Safety of living donors is critical to the success of blood, tissue and organ transplantation. Structured and robust vigilance and surveillance systems exist as part of some national entities, but historically no global systems are in place to ensure conformity, harmonisation and the recognition of rare adverse events (AEs). The World Health Assembly has recently resolved to require AE/reaction (AE/R) reporting both nationally and globally. The World Marrow Donor Association (WMDA) is an international organisation promoting the safety of unrelated donors and progenitor cell products for use in haematopoietic progenitor cell (HPC) transplantation. To address this issue, we established a system for collecting, collating, analysing, distributing and reacting to serious adverse events and reactions (SAE/R) in unrelated HPC donors. The WMDA successfully instituted this reporting system with 203 SAE/R reported in 2011. The committee generated two rapid reports, reacting to specific SAE/R, resulting in practice changing policies. The system has a robust governance structure, formal feedback to the WMDA membership and transparent information flows to other agencies, specialist physicians and transplant programs and the general public.

Cell surface structures influence lung clearance rate of systemically infused mesenchymal stromal cells

The promising clinical effects of mesenchymal stromal/stem cells (MSCs) rely especially on paracrine and nonimmunogenic mechanisms. Delivery routes are essential for the efficacy of cell therapy and systemic delivery by infusion is the obvious goal for many forms of MSC therapy. Lung adhesion of MSCs might, however, be a major obstacle yet to overcome. Current knowledge does not allow us to make sound conclusions whether MSC lung entrapment is harmful or beneficial, and thus we wanted to explore MSC lung adhesion in greater detail. We found a striking difference in the lung clearance rate of systemically infused MSCs derived from two different clinical sources, namely bone marrow (BM-MSCs) and umbilical cord blood (UCB-MSCs). The BM-MSCs and UCB-MSCs used in this study differed in cell size, but our results also indicated other mechanisms behind the lung adherence. A detailed analysis of the cell surface profiles revealed differences in the expression of relevant adhesion molecules. The UCB-MSCs had higher expression levels of α4 integrin (CD49d, VLA-4), α6 integrin (CD49f, VLA-6), and the hepatocyte growth factor receptor (c-Met) and a higher general fucosylation level. Strikingly, the level of CD49d and CD49f expression could be functionally linked with the lung clearance rate. Additionally, we saw a possible link between MSC lung adherence and higher fibronectin expression and we show that the expression of fibronectin increases with MSC culture confluence. Future studies should aim at developing methods of transiently modifying the cell surface structures in order to improve the delivery of therapeutic cells.

The Nordic prescription databases as a resource for pharmacoepidemiological research--a literature review

PURPOSE

All five Nordic countries have nationwide prescription databases covering all dispensed drugs, with potential for linkage to outcomes. The aim of this review is to present an overview of therapeutic areas studied and methods applied in pharmacoepidemiologic studies using data from these databases.

METHODS

The study consists of a Medline-based structured literature review of scientific papers published during 2005-2010 using data from the prescription databases in Denmark, Finland, Iceland, Norway, and Sweden, covering 25 million inhabitants. Relevant studies were analyzed in terms of pharmacological group, study population, outcomes examined, type of study (drug utilization vs. effect of drug therapy), country of origin, and extent of cross-national collaboration.

RESULTS

A total of 515 studies were identified. Of these, 262 were conducted in Denmark, 97 in Finland, 4 in Iceland, 87 in Norway, and 61 in Sweden. Four studies used data from more than one Nordic country. The most commonly studied drugs were those acting on the nervous system, followed by cardiovascular drugs and gastrointestinal/endocrine drugs. A total of 228 studies examined drug utilization and 263 focused on the effects and safety of drug therapy. Pregnant women were the most commonly studied population in safety studies, whereas prescribers' adherence to guidelines was the most frequent topic of drug utilization studies.

CONCLUSIONS

The Nordic prescription databases, with their possibility of record-linkage, represent an outstanding resource for assessing the beneficial and adverse effects of drug use in large populations, under routine care conditions, and with the potential for long-term follow-up.

Aging bone marrow mesenchymal stromal cells have altered membrane glycerophospholipid composition and functionality

Human mesenchymal stem/stromal cells (hMSC) are increasingly used in advanced cellular therapies. The clinical use of hMSCs demands sequential cell expansions. As it is well established that membrane glycerophospholipids (GPL) provide precursors for signaling lipids that modulate cellular functions, we studied the effect of the donor's age and cell doublings on the GPL profile of human bone marrow MSC (hBMSC). The hBMSCs, which were harvested from five young and five old adults, showed clear compositional changes during expansion seen at the level of lipid classes, lipid species, and acyl chains. The ratio of phosphatidylinositol to phosphatidylserine increased toward the late-passage samples. Furthermore, 20:4n-6-containing species of phosphatidylcholine and phosphatidylethanolamine accumulated while the species containing monounsaturated fatty acids (FA) decreased during passaging. Additionally, in the total FA pool of the cells, 20:4n-6 increased, which happened at the expense of n-3 polyunsaturated FAs, especially 22:6n-3. The GPL and FA correlated with the decreased immunosuppressive capacity of hBMSCs during expansion. Our observations were further supported by alterations in the gene expression levels of several enzymes involved in lipid metabolism and immunomodulation. The results show that extensive expansion of hBMSCs harmfully modulates membrane GPLs, affecting lipid signaling and eventually impairing functionality.

Analysis of the adequate size of a cord blood bank and comparison of HLA haplotype distributions between four populations

The number of units and especially the number of different HLA haplotypes present in a cord blood (CB) bank is a crucial determinant of its usefulness. We generated data relevant to the development of our national CB in Finland. The HLA haplotype distribution was examined between specific populations. We developed graphical ways of data presentation that enable easy visualization of differences. First, we estimated the optimal size of a CB bank for Finland and found that approximately 1700 units are needed to provide a 5/6 HLA-matched donor for 80% of Finnish patients. Secondly, we evaluated HLA haplotype distributions between four locations, Finland, Japan, Sweden and Belgium. Our results showed that the Japanese Tokyo Cord Blood Bank differs in both the frequency and distribution of haplotypes from the European banks. The European banks (Finnish Cord Blood Registry, The Swedish National Cord Blood Bank, and Marrow Donor Program-Belgium) have similar frequencies of common haplotypes, but 26% of the haplotypes in the Finnish CB bank are unique, which justifies the existence of a national bank. The tendency to a homogenous HLA haplotype distribution in banks underlines the need for targeting recruitment at the poorly represented minority populations.

End-stage renal disease and critical limb ischemia: a deadly combination?

OBJECTIVES

This study was planned to evaluate the prognostic impact of end-stage renal disease (ESRD) in patients with critical leg ischemia (CLI) undergoing infrainguinal revascularization.

MATERIALS AND METHODS

1425 patients who underwent infrainguinal revascularization for CLI were the subjects of the present analysis. Ninety-five patients had ESRD (eGFR < 15 ml/min/m²), and of them 66 (70%) underwent percutaneous transluminal angioplasty and 29 (30%) underwent bypass surgery.

RESULTS

ESRD patients had significantly lower overall survival (at 3-year, 27.1% vs. 59.7%, p < 0.0001), leg salvage (at 3-year, 57.7% vs. 83.0%, p < 0.0001), and amputation free survival (at 3-year, 16.2% vs. 52.9%, p < 0.0001) than patients with no or less severe renal failure. The difference in survival was even greater between 86 one-to-one propensity matched pairs (at 3-year, 23.1% vs. 67.3%, p < 0.0001). ESRD was an independent predictor of all-cause mortality (RR 2.46, 95%CI 1.85-3.26). Logistic regression showed that age ≥ 75 years was the only independent predictor of 1-year all-cause mortality (OR 4.92, 95%CI 1.32-18.36). Classification and regression tree analysis showed that age ≥ 75 years and, among younger patients, bypass surgery for leg ulcer and gangrene were associated with significantly higher 1-year mortality

CONCLUSIONS

Lower limb revascularization in patients with CLI and end-stage renal failure is associated with favourable leg salvage. However, these patients have a very poor survival and this may jeopardize any attempt of revascularization. Further studies are needed to identify ESRD patients with acceptable life expectancy and who may benefit from lower limb revascularization.

Predictors of Failure of Endovascular Revascularization for Critical Limb Ischemia

Background and Aims:

To characterize predictors of failure when treating critical limb ischemia (CLI) patients with an endovascular intervention as the first-line strategy.

Patients and Methods:

This retrospective, registry-based study included 217 consecutive patients with 240 chronic critically ischemic limbs treated with infrainguinal percutaneous transluminal angioplasty (PTA) during 2006–2007 at Helsinki University Central Hospital, Finland. The primary outcome measures were death, major (above-ankle) amputation, and the need for surgical re-intervention within 6 months after the primary procedure. The secondary outcome measures were overall major amputation and survival rates as well as the overall need for surgical or any other (surgical or endovascular) type of re-intervention. Predictors of outcome endpoints were identified with a univariate screen, and a Cox regression model was used in the multivariate analysis.

Results:

Compared to ulcer, gangrene was significantly more strongly associated with amputation within 6 months post-procedurally as well as during the whole follow-up period (p ≤ 0.028). The patient's inability to walk upon hospital arrival was a significant predictor of death, amputation and surgical re-intervention. Mediasclerotic ankle-brachial index (ABI) was an independent predictor of amputation as well as endovascular re-interventions.

Conclusions:

The strong predictors of poor outcome after endovascular revascularization for patients with CLI are cardiac morbidity, the inability to ambulate upon hospital arrival, and gangrene as a manifestation of CLI. The risk of amputation seems to be significantly higher for gangrene than for ulcer and this matter should be taken into account in the clinical classifications for CLI.

Side-to-side differences in bone strength in master jumpers and sprinters

INTRODUCTION

This study evaluated side-to-side difference in tibial bone structure, calf muscle cross-sectional area (CSA) and hopping force in master athletes as a result of training for sports with different magnitudes of inter-leg loading difference.

METHODS

Tibial bone parameters (at 4%, 14%, 38% and 66% tibial length proximal to distal end), muscle CSA (at 66% tibial length) and hopping forces of both legs of 51 master athletes (conditioned jumpers, conditioned triple jumpers, unconditioned jumpers, hurdlers and sprinters) were examined using pQCT. In epiphyseal 4% slice bone CSA (Ar.tot), total BMC (vBMC.tot), trabecular BMC (vBMC.tb) cortical BMC (vBMC.ct), and trabecular BMD (vBMD.tb) were measured. In diaphyseal slices, Ar.tot, vBMC.ct, cortical density (vBMD.ct), cross-sectional moment of inertia (CSMI) and calf muscle CSA (MuscA) were examined.

RESULTS

In conditioned jumpers, side-to-side differences in favour of take-off leg were found in 4% slice in vBMC.tb (+4.1%) (P<0.05). A side-to-side difference was found in 66% slice vBMC.ct and CSMI (both P<0.05), with conditioned jumper (+2.8% and 6.6%) and triple jumper (+2.7% and 7.2%) values higher than other groups.

CONCLUSION

The results suggest that regular training in high-impact sports with uneven lower limb loading results in side-to-side differences in skeletal adaptation independent of age and gender, suggesting that high-impact exercise is effective in maintaining bone strength throughout human lifespan.

The role of chronic kidney disease as a predictor of outcome after revascularisation of the ulcerated diabetic foot

AIMS/HYPOTHESIS

The aim of the study was to stratify the risk of diabetic patients with leg ulcer or gangrene undergoing infrainguinal revascularisation for critical limb ischaemia.

METHODS

The study cohort included 732 revascularisation procedures performed in 597 diabetic patients with ulcer or gangrene. Logistic regression and CART analysis were used for identification of predictors of 1-year outcome.

RESULTS

Logistic regression showed that chronic kidney disease (CKD) class (OR 1.38, 95% CI 1.16, 1.65) was an independent predictor of 1-year leg salvage (area under the receiver operating characteristic [ROC] curve 0.60, 95% CI 0.54, 0.65). The terminal nodes of the CART for 1-year leg salvage were CKD classes 4-5, the level (infrapopliteal vs femoropopliteal revascularisation), type of revascularisation (bypass surgery vs percutaneous transluminal angioplasty) and gangrene (area under the ROC curve 0.62, 95% CI 0.57, 0.68). Logistic regression showed that pulmonary disease (OR 1.76, 95% CI 1.11, 2.78), CKD class (OR 1.43, 95% CI 1.24, 1.65), foot gangrene (OR 1.76, 95% CI 1.21, 2.60) and patient age (OR 1.02, 95% CI 1.01, 1.04) were independent predictors of 1-year amputation-free survival (area under the ROC curve 0.65, 95% CI 0.60, 0.69). The terminal nodes of the CART for 1-year amputation-free survival were CKD classes 3-5, patient's age of ≥ 75 years and foot gangrene (area under the ROC curve 0.64, 95% CI 0.60, 0.68).

CONCLUSIONS/INTERPRETATION

CKD is a formidable risk factor for poor intermediate outcome after infrainguinal revascularisation in diabetic patients with foot ulcer or gangrene. CART analysis indicates that foot gangrene is also a significant risk factor for adverse outcome.

Rac deletion in osteoclasts causes severe osteopetrosis

Cdc42 mediates bone resorption principally by stimulating osteoclastogenesis. Whether its sister GTPase, Rac, meaningfully impacts upon the osteoclast and, if so, by what means, is unclear. We find that whereas deletion of Rac1 or Rac2 alone has no effect, variable reduction of Rac1 in osteoclastic cells of Rac2(-/-) mice causes severe osteopetrosis. Osteoclasts lacking Rac1 and Rac2 in combination (Rac double-knockout, RacDKO), fail to effectively resorb bone. By contrast, osteoclasts are abundant in RacDKO osteopetrotic mice and, unlike those deficient in Cdc42, express the maturation markers of the cells normally. Hence, the osteopetrotic lesion of RacDKO mice largely reflects impaired function, and not arrested differentiation, of the resorptive polykaryon. The dysfunction of RacDKO osteoclasts represents failed cytoskeleton organization as evidenced by reduced motility of the cells and their inability to spread or generate the key resorptive organelles (i.e. actin rings and ruffled borders), which is accompanied by abnormal Arp3 distribution. The cytoskeleton-organizing capacity of Rac1 is mediated through its 20-amino-acid effector domain. Thus, Rac1 and Rac2 are mutually compensatory. Unlike Cdc42 deficiency, their combined absence does not impact upon differentiation but promotes severe osteopetrosis by dysregulating the osteoclast cytoskeleton.

Infrainguinal percutaneous transluminal angioplasty or bypass surgery in patients aged 80 years and older with critical leg ischaemia

Background

Infrainguinal revascularization for critical leg ischaemia (CLI) in patients aged 80 years and over is associated with increased operative risk. The aim was to compare the results of percutaneous transluminal angioplasty (PTA) and bypass surgery in these patients.

Methods

Some 584 consecutive patients aged at least 80 years treated with either PTA (277) or bypass surgery (307) for CLI between 2000 and 2007 were included in this study.

Results

After 2 years PTA achieved better results than bypass surgery (leg salvage: 85·4 versus 78·7 per cent, P = 0·039; survival: 57·7 versus 52·3 per cent, P = 0·014; amputation-free survival (AFS): 53·0 versus 44·9 per cent, P = 0·005). Cox regression analysis showed that increased age (relative risk (RR) 1·05, 95 per cent confidence interval 1·02 to 1·08), decreased estimated glomerular filtration rate (RR 0·99, 0·99 to 1·00), diabetes (RR 1·30, 1·04 to 1·62), coronary artery disease (RR 1·36, 1·05 to 1·75) and bypass surgery (RR 1·55, 1·24 to 1·93) were associated with decreased AFS. In 95 propensity score-matched pairs, leg salvage at 2 years (88 versus 75 per cent; P = 0·010) and AFS (53 versus 45 per cent; P = 0·033) were significantly better after PTA. Classification and regression tree analysis suggested that PTA was associated with better 1-year AFS, especially in patients with coronary artery disease (63·8 versus 48·9 per cent; P = 0·008).

Conclusion

When feasible, a strategy of PTA first appears to achieve better results than infrainguinal bypass surgery in patients aged 80 years and older.

Clinical and immunological overlap between autoimmune lymphoproliferative syndrome and common variable immunodeficiency

Autoimmune lymphoproliferative syndrome (ALPS) is mainly caused by defects in the CD95 pathway. Raised CD3+TCRαβ+CD4-CD8- double negative T cells and impaired T cell apoptosis are hallmarks of the disease. In contrast, the B cell compartment has been less well studied. We found an altered distribution of B cell subsets with raised transitional B cells and reduced marginal zone B cells, switched memory B cells and plasma blasts in most of 22 analyzed ALPS patients. Moreover, 5 out of 66 ALPS patients presented with low IgG and susceptibility to infection revealing a significant overlap between ALPS and common variable immunodeficiency (CVID). In patients presenting with lymphoproliferation, cytopenia, hypogammaglobulinemia and impaired B cell differentiation, serum biomarkers were helpful in addition to apoptosis tests for the identification of ALPS patients. Our observations may indicate a role for apoptosis defects in some diseases currently classified as CVID.